Howling Puppy: Heart broken moment

Little Pepper was so attached to me when he was 4 months old. I left him alone when I went to work. I discovered this moment from my home camera. I knew the little one was so lonely and not used to the new house we just moved in. I was so heart broken when hearing him howling all the time. Now Pepper is getting much better and he can stay at home by himself.I always rush going home after work and take him out for a walk.